:root {
  --ink: #0b1f35;
  --navy: #07192d;
  --blue: #0756c9;
  --cyan: #35d5eb;
  --paper: #f5f9fd;
  --line: #d4e1ee;
  --muted: #556b82;
  --white: #fff;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 92px; }
body { margin: 0; color: var(--ink); background: var(--white); font-family: "Noto Sans JP", "Yu Gothic", sans-serif; line-height: 1.85; letter-spacing: 0; }
a { color: inherit; }
img { display: block; max-width: 100%; }

.guide-header { position: sticky; top: 0; z-index: 20; min-height: 76px; padding: 12px clamp(24px, 5vw, 72px); display: flex; align-items: center; justify-content: space-between; gap: 28px; color: white; background: rgba(5, 19, 35, .96); border-bottom: 1px solid rgba(53, 213, 235, .28); }
.guide-brand img { width: 158px; }
.guide-header nav { display: flex; align-items: center; gap: 26px; font-size: 14px; font-weight: 800; }
.guide-header nav a { text-decoration: none; white-space: nowrap; }
.guide-header nav a:hover { color: var(--cyan); }
.guide-header .guide-header-cta { padding: 10px 18px; color: white; background: var(--blue); }

main { overflow: hidden; }
.breadcrumbs { width: min(1180px, calc(100% - 48px)); margin: 18px auto; display: flex; gap: 10px; color: var(--muted); font-size: 13px; }
.breadcrumbs a { font-weight: 800; }

.guide-hero { min-height: 670px; padding: 80px max(6vw, 28px); display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(420px, .95fr); align-items: center; gap: 72px; color: white; background: var(--navy); }
.guide-hero-copy { max-width: 760px; }
.guide-kicker { margin: 0 0 16px; color: #15bdd7; font-size: 12px; font-weight: 900; letter-spacing: .16em; }
.guide-hero .guide-kicker { color: #71eafa; }
.guide-hero h1 { margin: 0; font-family: "Yu Mincho", "Hiragino Mincho ProN", serif; font-size: clamp(46px, 6vw, 82px); font-weight: 600; line-height: 1.18; }
.guide-hero h1 span { color: var(--cyan); }
.guide-lead { max-width: 760px; margin: 28px 0 0; color: #e1edf8; font-size: 18px; line-height: 2; }
.guide-actions { margin-top: 34px; display: flex; flex-wrap: wrap; gap: 12px; }
.guide-primary, .guide-secondary { min-height: 54px; padding: 13px 23px; display: inline-flex; align-items: center; justify-content: center; font-weight: 900; text-decoration: none; }
.guide-primary { color: white; background: var(--blue); }
.guide-secondary { color: var(--ink); background: white; border: 1px solid var(--line); }
.guide-hero-media { margin: 0; }
.guide-hero-media img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; object-position: center; border: 1px solid rgba(255,255,255,.25); }
.guide-hero-media figcaption { margin-top: 12px; color: #b9cbe0; font-size: 12px; }

.answer-band { padding: 56px max(8vw, 28px); color: white; background: #0756c9; }
.answer-band h2 { margin: 0; font-size: clamp(30px, 4vw, 48px); }
.answer-band p:last-child { max-width: 1040px; margin: 18px 0 0; font-size: 19px; }
.answer-band .guide-kicker { color: #b9f7ff; }

.guide-section { width: min(1180px, calc(100% - 48px)); margin: 0 auto; padding: 100px 0; scroll-margin-top: 92px; }
.section-heading { margin-bottom: 42px; }
.section-heading h2 { margin: 0; font-family: "Yu Mincho", "Hiragino Mincho ProN", serif; font-size: clamp(34px, 5vw, 58px); line-height: 1.3; }
.section-intro, .prose { max-width: 900px; }
.prose p, .section-intro { color: #314a63; font-size: 17px; }
.prose p + p { margin-top: 22px; }

.comparison-table { margin-top: 44px; overflow-x: auto; border: 1px solid var(--line); }
.comparison-table table { width: 100%; min-width: 720px; border-collapse: collapse; }
.comparison-table th, .comparison-table td { padding: 18px 20px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.comparison-table thead th { color: white; background: #0b3761; }
.comparison-table tbody th { width: 170px; color: #064e9e; background: #eef6fd; }

.contrast-section { width: 100%; padding-inline: max(calc((100% - 1180px) / 2), 24px); color: white; background: #0b2b4d; }
.contrast-section .guide-kicker { color: #6ceafa; }
.two-column-copy { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1px; background: rgba(255,255,255,.25); border: 1px solid rgba(255,255,255,.25); }
.two-column-copy article { padding: 34px; background: #0b2b4d; }
.two-column-copy h3 { margin: 0 0 14px; font-size: 23px; }
.two-column-copy p { margin: 0; color: #d6e4f0; }

.wide-heading { display: grid; grid-template-columns: 1fr minmax(300px, .7fr); align-items: end; gap: 50px; }
.wide-heading > p { margin: 0; color: var(--muted); }
.measure-list { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.measure-list li { padding: 28px 0; display: grid; grid-template-columns: 82px 1fr; gap: 28px; border-bottom: 1px solid var(--line); }
.measure-list li > span { color: var(--blue); font-size: 22px; font-weight: 900; }
.measure-list h3 { margin: 0 0 7px; font-size: 22px; }
.measure-list p { margin: 0; color: var(--muted); }

.evidence-section { width: 100%; padding-inline: max(calc((100% - 1180px) / 2), 24px); background: #edf8fb; }
.axis-list { margin: 38px 0 30px; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); border-top: 1px solid #b9dce4; border-left: 1px solid #b9dce4; }
.axis-list article { min-height: 220px; padding: 24px 20px; border-right: 1px solid #b9dce4; border-bottom: 1px solid #b9dce4; background: white; }
.axis-list strong { color: #0756c9; font-size: 17px; }
.axis-list p { margin: 14px 0 0; color: var(--muted); font-size: 14px; }
.text-link { color: #064e9e; font-weight: 900; text-underline-offset: 6px; }

.measurement-section { width: 100%; padding-inline: max(calc((100% - 1180px) / 2), 24px); color: white; background: #07192d; }
.measurement-section .guide-kicker { color: #6ceafa; }
.measurement-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1px; background: rgba(255,255,255,.25); border: 1px solid rgba(255,255,255,.25); }
.measurement-grid article { padding: 30px; background: #07192d; }
.measurement-grid span { color: #6ceafa; font-size: 12px; font-weight: 900; text-transform: uppercase; }
.measurement-grid h3 { margin: 10px 0 12px; font-size: 22px; }
.measurement-grid p { margin: 0; color: #d5e2ef; }

.warning-section ul { margin: 0; padding: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; list-style: none; }
.warning-section li { padding: 25px; color: #435970; background: #fff7f3; border-left: 4px solid #e65c25; }
.warning-section strong { color: var(--ink); }

.guide-faq { border-top: 1px solid var(--line); }
.guide-faq details { border-bottom: 1px solid var(--line); }
.guide-faq summary { padding: 24px 44px 24px 0; position: relative; cursor: pointer; font-size: 18px; font-weight: 900; list-style: none; }
.guide-faq summary::-webkit-details-marker { display: none; }
.guide-faq summary::after { content: "+"; position: absolute; right: 8px; top: 17px; color: var(--blue); font-size: 28px; }
.guide-faq details[open] summary::after { content: "−"; }
.guide-faq details p { max-width: 900px; margin: 0; padding: 0 50px 24px 0; color: var(--muted); }

.sources-section { padding: 70px max(8vw, 28px); color: #344b61; background: var(--paper); }
.sources-section h2 { margin: 0; color: var(--ink); font-size: 28px; }
.sources-section p { max-width: 900px; }
.sources-section ul { margin: 20px 0 0; padding-left: 22px; }
.sources-section a { color: #0756c9; }

.guide-final-cta { padding: 72px max(8vw, 28px); display: flex; align-items: center; justify-content: space-between; gap: 50px; color: white; background: #0756c9; }
.guide-final-cta h2 { margin: 0; font-size: clamp(30px, 4vw, 48px); }
.guide-final-cta p:not(.guide-kicker) { margin: 14px 0 0; }
.guide-final-cta .guide-kicker { color: #b9f7ff; }
.guide-final-cta .guide-actions { margin-top: 0; flex: 0 0 auto; }

.guide-footer { padding: 36px max(5vw, 24px); display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 36px; color: #d6e3ef; background: #040e19; font-size: 13px; }
.guide-footer img { width: 142px; }
.guide-footer nav { display: flex; flex-wrap: wrap; justify-content: center; gap: 18px; }
.guide-footer nav a { text-decoration: none; }
.guide-footer p { margin: 0; }

@media (max-width: 980px) {
  html { scroll-padding-top: 72px; }
  .guide-header { min-height: 66px; padding: 10px 18px; }
  .guide-header nav a:not(.guide-header-cta) { display: none; }
  .guide-hero { min-height: auto; grid-template-columns: 1fr; gap: 44px; padding-block: 62px; }
  .guide-hero-media { max-width: 680px; }
  .guide-section { scroll-margin-top: 72px; }
  .wide-heading { grid-template-columns: 1fr; gap: 18px; }
  .axis-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .measurement-grid { grid-template-columns: 1fr; }
  .guide-final-cta { align-items: flex-start; flex-direction: column; }
  .guide-footer { grid-template-columns: 1fr; justify-items: start; }
  .guide-footer nav { justify-content: flex-start; }
}

@media (max-width: 620px) {
  .guide-brand img { width: 138px; }
  .guide-header .guide-header-cta { padding: 9px 12px; }
  .breadcrumbs { width: calc(100% - 32px); }
  .guide-hero { padding: 48px 20px; }
  .guide-hero h1 { font-size: 40px; }
  .guide-lead { font-size: 16px; }
  .guide-actions, .guide-primary, .guide-secondary { width: 100%; }
  .answer-band { padding: 44px 20px; }
  .answer-band p:last-child { font-size: 17px; }
  .guide-section { width: calc(100% - 40px); padding: 72px 0; }
  .contrast-section, .evidence-section, .measurement-section { width: 100%; padding-inline: 20px; }
  .two-column-copy { grid-template-columns: 1fr; }
  .two-column-copy article { padding: 24px; }
  .measure-list li { grid-template-columns: 48px 1fr; gap: 14px; }
  .axis-list { grid-template-columns: 1fr; }
  .axis-list article { min-height: 0; }
  .warning-section ul { grid-template-columns: 1fr; }
  .guide-final-cta { padding: 56px 20px; }
  .guide-final-cta .guide-actions { width: 100%; }
}